Cement finishing machine



Feb. 22, 1944. H. D. ALLEN CEMENT FINISHING MACHINE s Sheets-Shee t 1 Filed July 17, 1942 gwuc wto'o flame: Q 1411 EN,

Feb. 22, 1944.

H. D. ALLEN 2,342,445

CEMENT FINISHING MACHINE Filed July 17, 1942 3 Sheets-Sheet s Patented Feb. 22, 1944 UNITED STATES FATENT OFFICE CEMENT FINISHING MACHINE Horace D. Allen, Columbia, S. 0., assignor of onehalf to 0. S. C.

Stanley Smith, Richland County,

Application July 17, 1942, Serial No. 451,351

Claims.

in weight, of simple construction and may be easily transported or carried from one point to 1 another.

The machine utilizes one or more smoothing or finishing blades or trowels, preferably of the rotatable type, and in conjunction therewith a surface conditioning device which conditions the cementitious surface for the finishing blades so that the latter may be operated at a reduced speed of rotation and working pressure while at the same time finishing the surface acted upon more effectively and in a shorter space of time than has been possible with prior known ma-.

chines.

One of the factors which gave rise to the conception and reduction to practice of the present improved machine was the desire to improve upon finishing or surfacing machines of the rotary blade type utilizing the gravitational weight of the machine and its driving member or motor to control the working pressure on the smoothing blades or trowels. Such machines are difficult to manipulate, even by skilled operators, and are heavy and cumbersome, rendering it awkward to transport or carry the machine from one point to another, and the power consumption is relatively high. Furthermore, unless the cementitious surface is properly conditioned, the finishing operation leaves much to be desired, and in order to produce a relatively hard, dense surface, the machine must embody a relatively heavy weight which is generally imposed directly upon the vertical axis of the rotating blade unit. Again, such machines are difficult to guide, the usual procedure being to vary the pressure on opposite sides of the diametral axis of the blade unit and which will result in a non-uniform surface unless considerable skill and care is utilized in the operation.

Another object of the invention therefore is to provide a machine which will embody the desirable features of the rotating blade type of machine while at the same time will lack the objectionable features thereof.

Another object is to provide a concret surfacing machine capable of producing a surface according to specifications, viz: a so-called float" surface such as is generally specified for concrete pavements, roadways, etc., or a trowel finish such as is generally specified for heavy duty floors or those requiring a highly finished surface. 1

Further objects of the invention include: the provision of a cement or concrete smoothing and finishing machine of simple, low cost construction embodying a power unit which may be easily removed and used elsewhere and just as easily replaced; a machine of the type specified which is balanced to obtain the most effective surfacing operation and is sufiiciently light in weight to enable it to be carried in one hand; and to generally improve and simplify cement or concrete finishing machines.

The foregoing and other objects and advantages will become apparent in view of the following description taken in conjunction with the drawings, wherein:

Figure 1 is a plan view of a machine in accordance with the invention;

Figs. 2 and 3 are respectively, views in side and front elevation thereof;

Fig. 4, a substantially central longitudinal vertical section of the machine;

Fig. 5, a view in plan of a machin having a modified or alternate type of frame with respect to the machine of Figs. 1 to 4, inclusive, and also illustrating attachments for use in obtaining a trowel finish;

Fig. 6, a view in side elevation of the machine of Fig. 5;

Fig. 7, a detail perspective of one of the finishingblades to be used when it is desiredto obtain a trowel finish; and

' Fig. 8, a view similar to Fig. 7 of a surfaceconditioning attachment.

Referring to the drawings in detail and first to Figs. 1 to 4, inclusive, any suitable frame may be utilized for the machine. That illustrated is of the skeleton type and comprises an elongated base member in the form of a channel-shaped beam or bar I!) which forms a support for a rear bearing bar II and an upright power unit supporting member 12. The bar I I has its front end secured as by welding to the base member H] as indicated at H, the intermediate portion of the her being bent upwardly and then projected rearwardly to form a support for a frame member 93, having a vertical portion or leg, l3 and a horizontal portion l3" which provides a carrying handle. member I3" is connected as bybolt M to the upper end of the frame member l2, said member The horizontal portion or frame 13 being slotted as at l where the bolt M projects therethro-ugh to render the frame member i2 and the parts carried thereby horizontally adjustable. Likewise, the lower end of the frame member i2 is secured to the base beam It] by means of bolt l6 projecting through a slot 51.

'At the front end of the machine is mounted a triangular yoke it which at its upper end is connected to the front end ofthe frame member l3" as by bolt l9 extending through an adjusting slot 20. A cross bar 2| is connected between the lower ends of the yoke 18, said ends being projected downardly beyond said bar to provide bearings for a shaft 22 mounting what is herein termed a leveling roller 23 and the function of which will be hereinafter more fully described.

The front end of the base member I 0 is slotted as at 24 note Fig. 4 to adjustably receive a swivel bolt 25 by means of which the transverse. bar 2| is connected to the base member in a manner such as to permit theyoke l-3 andthe roller 2'3- tobe turned or rotated about a vertical axis; or' more properly stated, topermit. the machine as a whole to be swung arcuately about said roller, note the arcuate lines in Fig. 1.

To definitely limit-the degree of swivelingor rotation of the machine with respect to. the roller 23; means such as flexible straps 26 andZt are connected at 21tothe transverse bar 2| and at 21 to the frame member: Ill. straps 26; 26"", while not being absolutely necessary; are of advantage in that they facilitate effective operation of themachine-.

The-upper horizontal: frame member" l 3 is in! clined upwardly-'at its. front endand has secured:

thereto a handle bar 28 adapted to receive-a handle 2-9 to facilitate manipulation of the" machine.

The handle is preferably insulated to prevent possibleshock should a short occur when using" electric power.

At the rear end of the machine is mounted: a

series of rotating blade unitscomprising finish ingblades or trowels 30', Ma; and tfib; each. of which is of identical constructiorr'and a description of one. will'therefore suffice for all. These blades are each preferably" formed. with a con- I vex working surface, the blade inthe present instance being'comprised of a strip of suitable material-such as" hardened steel having a concavo-convex shape in cross section. Secured to opposite extremities of the bladeare the, lower ends of mountingbolts' or rods 31 which project vertically and at their upper ends are adjustably secured as by nuts 32 to; spaced brackets or holders 33, 33', the latter at their outer ends being rigidly connected to a guard ring, 34 and at their inner ends to the peripheral flange of a bearing hub 35 formed with a central socket 351). into. which. projects the lower end of" the hub 36 of a drive wheel. or pulley 3.6. The pulley 35 is formed with acentral bore through which projects' a rod or 'shaftsl having a lower headed end engaging the bottom wall of the socket135b, the

upper'end of the shaft'or rod 31 being threaded and projecting through the rear end of the frame member ll. Securing nut 38. and lock nut 39 holds the. shaft 3Ttogether with the parts carried thereby in place.

By adjusting nuts 32, the slope of the blades may-"in turn be adjusted to'tobtain the most effective: working position;

The rotating blade unit is driven by means of 'a power unit here shown as comprising an electric drill motor4il: which" is removably connected; to the frame of themachine'by means oftuppen and These flexible:

u for, finishing operations.

lower brackets or blocks M and 42 secured to the vertical frame member [2 by means of clamps 4| and 42' and bolts 4| and 42". The lower bracket 2-2 is in the form of a bearing block which forms a bearing support for the motor and the armature or driving shaft i3 of the latter. The motor 50 is provided with a switch lever 44 and-a carrying handle 45.

The drive or armature shaft 43 of the motor it has secured on the lower end thereof a pulley adapted to receive a driving belt 41 which engages over the driving disc or pulley 36 so that the drive may be transmitted from said motor to the rotary finishing blades 3%, 39a and 3%.

A brief'statement of operation of the machine and certain of its. advantages follows:

Assuming that it is desired to finish the surface of freshly lai'dconcrete or cement, the machine may be carried by the handle portion l3" to the point of operation and the motor it) turned on, whereupon. the finished blade unit will start to rotate. The machine as herein shown is'adaptcd to. be moved in a direction following the operator so that any foot prints or impressions will be eradicated. The ope ator grasps the handle 29 and controls the'weightimposed on the finishingblades or trowels by pressing downwardly or lifting upwardly on said handle. As the machineis moved overthesurface to be finished, the roller 23 acts on said surface to level and properly con-- dition the same for the finishing blades, any projecting pebbles, stones or the like, being pressed into the-soft cement while at the same time irreg ulariti'es are leveled and brought down to the proper plane to be acted upon by the blades. In

this manner, the surface of the-floor or pavement isplaced in a condition so that the finishing blades will more effectively operate within the shortestpossible space of time and" at a relatively slow speed of rotation. In practice, the speed of rotation is such that there is noslinging of water or cement by the blades.

In Fig. '1, the arcuate arrowhead line and'the similar dot and dash lines are used to illustrate how the finishing blade unit may be swiveled or turned from side to sideto coverthe surface acted uponand conditioned by the roller 23' and the surface adjacent said rolled area. Thus should the roller leave any lines, at its opposite ends, the

blades may be manipulated to completely eradicate the same, as well as finish any portion of the surface within the range of the blades. The weight imposed on the finishing blades is not fixed, as in conventional machines of the rotating blade type, but is governed entirely by the operator. This is an important factor, since concrete may be effectively finished irrespective of whether or notit is in the exact condition most susceptible For example, where. a certain fixed Weight would cause the, blades to work toe. deeply into. the, surface, with the, present machine, this weightv may be centrcl-led to avoid thisv undesirable operation.

By theinherent nature of the present. machine, it may be balanced to obtain the most. efiective surfacing action and made relatively light. in Weight. In fact, machines weighing approximately pounds have been found highly satis-. factory. A: machine ofthis weight may be easily carried in one hand by a workman or operator, and it may be lifted straight up: from a finished surface and transported to another point without leaving marks or other undesirable impressions; The driving unit or motor 49' may be easily re,-

moved at any time desired and used in some other machine. For example, in practice I have found that an electric drill motor may be used as the driving unit without any alterations whatsoever except to remove the drill bit and replace it with the shaft 43 and pulley 46. Furthermore, the machine may be easily shipped in a knockeddown condition, the roller and blade units together with the power unit being removable from the frame and capable of being arranged in a compact bundle or crate.

By adjusting the roller 23 together with the triangular yoke or frame member [8 forwardly or rearwardly, the gravitational weight of the machine may be shifted and the balanced adjusted.

As heretofore noted, the improved surfacing machine is adapted to provide either a so called float surface such as is generally specified for pavements and roadways, or a flat trowel or hard finish, such as is generally specified for heavy duty floors; and the machine illustrated in Figs. 5, 6 and 7 has been constructed with this in view. The frame of this machine comprises an elongated base member in the form of a beam or bar 50 having secured thereon a hanger bracket or yoke which in turn forms a support for a frame member generally indicated at 52 and having a rear inclined portion or leg 52' and a horizontal portion 52" which may also serve as a carrying handle. A vertical frame member 53 is adjustably secured at its lower end to the base bar 50 and its upper end to the horizontal portion 52" of the frame member 52, the connection being made for horizontal adjustment as in the form of the machine first described by providing slots to receive the securing bolts for these parts.

The front or leading end of the base member 50 is formed with a series of spaced holes 54, to provide a mounting for a surface-conditioning unit comprising a transversely disposed, elongated member 55 having a substantially flat working surface with its opposite marginal edges bent or inclined upwardly as at 55, said conditioning member being connected to the base frame 50 as by means of a hangar bolt or rod 56, the lower extremity of which is connected to the trowel 55 and reinforced by means of bracket legs 51 and 58, thereby providing a substantially rigid connection between the hangar rod 55 and member 55.

This surface-conditioning member 55 has a function analagous to the roller 23 in the machine of Figs. 1 to 4, inclusive, in that it prepares the surface for finishing blades to be subsequently described. For certain types of surfaces, this member 55 may be used in place of the roller 23, as for example, were it desired to obtain a more finished surface.

A conditioning unit of the roller type which may be used in conjunction with or in place of the conditioning member 55 is illustrated in Fig. 8 and generally indicated at 55a, said roller being provided with a shaft 55b carried by hearing bracket 55c, the latter being suspended from hanger rod or shaft 56a.

The function and operation of the trowel member 55 and roller member 55a will be more fully hereinafter described.

The base member 50 and the upper horizontal portion 52" of the frame member 52 are rigidly connected by means of an upright 59 which at its upper end is projected outwardly at an incline as at 59' and has connected thereto a handle 60, preferably insulated in a manner similar to the handle 29.

The rear end of the machine is constructed to accommodate a rotating finishing unit comprisin a series of blades 6|, Bla, Blb which may be substantially identical to the blades 30, 30a and 30b of the machine of Figs. 1 to 4, inclusive. The leading edge of each blade is formed with spaced holes for mounting bolts 62 and whereby a finishing blade or trowel 63, note particularly Fig. 7, may be removably secured thereto.

The blades 6| which support the finishing or trowel blades 63 are in turn adjustably supported from the central portion of a pulley 64 by means of bolts 65 which at their lower ends are spotwelded to the blade BI and at their upper ends are threaded and projected through the central or body portion of pulley 64 and are adjustably secured thereto by upper and lower nuts 66 and 66'. The pulley 64 may be made of pressed sheet steel in a manner similar to the ordinar disk wheel commonly used on automobiles.

The pulley and blade-mounting wheel 64 is carried by a vertical shaft 61 which at its lower end is provided with a head 61. The shaft 67 project through a bearing 68 mounted in the rear extremity of the base member 50 and also through bearings 69 mounted in the yoke 5|.

A guard ring or outer frame 10 encircles the pulley and blade unit, the ring being connected to the pulley wheel 64 by means of brackets II.

It will be noted that when the blades 6| are angularly adjusted in the manner described in conjunction with Figs. 1 to 4, inclusive, the angle of the finishing or auxiliary blades 63 are likewise adjusted. This is of considerable advantage as will be brought out in the subsequent description of the operation. The drive on the machine may be by means of a power unit, preferably an electric drill motor 12 which is secured to the frame member 53 by means of upper and lower brackets l3, 14, this power unit being substantially the same as that shown in the machine first described. The armature or drive shaft of the motor 12 has a pulley 15 secured on the lower end thereof, and power is taken from this pulley to the pulley wheel 64 by means of belt 16.

A description of the operation of the machine of Figs. 5, 6 and 7 together with certain inherent advantages, follows:

Assumingthat it is desired to provide a more highly finished surface than that obtainedwith the rotating finishing blade unit and conditioning roller of Figs. 1 to 4, inclusive, then the roller may be replaced by the member 55, and at the same time the finishing blades 63'may be secured to the blades El and adjusted to the desired or proper working angle. The surface to be prepared may be worked on within a period Of time such as will permit the concrete to set, and which time of course depends upon the mass and thickness of the concrete body as well as the surface on which the concrete is poured. For a relatively thick concrete body poured on relatively dry earth the setting time may be approximately two hours. The machine is then reciprocated or pulled towards the operator, or from left to right as shown in the drawings, o that the member 55 smooths the concrete and conditions the surface preparatory to being acted upon by the finishing blades 63. If desired, the roller 55a may be used in conjunction with the blade 55 to ensure leveling of all foot prints or protuberances before the surface is finished by the blades 63. The blades 53 operate in the manner simulating a hand trowel.

To obtain certain types of surfaces, the roller 4* ac -asst 5511mm b ti i fid, ni finl mfl'fi fil it the ...,.s:me.m er. ..d,-tl1.e.finishins lad s or the: roller may be: used in; place of the condt tioning member 515, with either the finishing blades, 58. or EL In certain instances, I first go over the surface with the rotating finishing blades 6,! or 38 to-ob-tain a rough finish and then follow up with the member 55 and finishing blades 63. However, this is only a matter of choice, it being understood that the roller and trowel attachments may be used wherever conditions render; it expedient.

The foregoing and other important advantages herein mentioned are inherent in the proved-machine; and it will be understood that certain changes in construction and design may be adopted without departing from the spirit or scope of the; invention as: defined by the appended claims.

What is claimed is:

1. A surface finishing machine for cement or concrete floors, pavements and the like, comprising a main frame, a substantially horizontally and transversely disposed roller carried by said frame, a shaft mounting said roller, a swiveled frame member mounting said shaft, a rotatable finishing unit including aplurality of spaced substantially horizontally and radially disposed blades carried by said frame to follow said roller; a source of power such as a motor having, a driving connection, with said finishing unit, said frame being provided with a handle, upward or downward" pressure on said handle causing said frame' to turn about said roller with the latter acting as a pivot to thereby regulate the working pressure of the blades, roller operating in advance of said finishing unit to condition the cement surface preparatory to the latter being acted upon by the of the unit.

2'. A surface finishing machine for cement or concrete floors, pavements and the like, comprising a frame, a substantially horizontallydisposecl roller carried: by said frame, a surfacefinishing unit also carried by said frame in spaced relation to said roller and including a plurality of radially-disposed blades adaptcdto operate upon the surface to be finished, said roller being adapted to. operate in "advance of said unit and condition the surface of the floor preparatory to said surface being acted upon by the blades of said finishing unit, the frame of the machine being adapted to be raised and lowered about the roller with the latter acting as a pivot to thereby control the working pressure on the blades, and means for rotating said finishing unit.

3; A surface finishing machine for cement or concrete fioors. pavements and the like, comprising a main frame, a substantially horizontally and tra-nsversly disposed roller carried by said frame, a shaft mounting said roller, a member supporting said shaft, said latter member being pivotally connected to said main frame, rotatable finishing unit including a plurality of spaced horizontally and radially disposed blades or trowels carried by said main frame in spaced relation to said roller and adapted to follow the latter when the machine is moved over the surface to be finished, a source of power such as a motor having a driving connection with said finishing unit, said motor being disposed so that its gravitational weight is imposed primarily on said roller, said frame being provided with a handle, upward or downward driving pressure on said handle causing said, frame to turn about said roller with the latter acting as a pivot to thereby regulate'the working pressure of said blades, lateral pressure on. said handle causing saidmain frame and rotatable finishing unit to swing in a substantially horizontal arcuate path with respect to said roller, the latter functioning, to condition the cement surface preparatory to said surface being acted upon by the blades.

l. A surface finishing machine for cement or concrete floors, pavements, and the like comprising a main frame including an elongated base member, a substantially horizontally and transversely disposed roller pivotally connected to said base member in a manner such that the machine may be swung arcuatcly in a substantially horizontal path with respect to said roller, a rotatable finishing unit including spaced horizontally and radially disposed blades carried by said frame to follow said roller, said base member maintaining said roller and finishing unit in operatively spaced relation, a,

power unit carried by said frame and having a connection with said finishing said frame being provided with a handle projecting forwardly beyond said roller, upward or downward pressure on said handle causing said frame to turn about saidrroller with the latter acting as a pivot to thereby regulate the working pressure of said blades, said roller conditioning the cement surface preparatory to the latter being acted upon by the blades.

5. A surface finishing machine for cement or concrete floors, pavements, and the like comprising a main frame, a substantially horizontally and transversely disposed roller carried by said frame, said roller being mounted in a manner such that the machine may be swung arcuately in a substantially horizontal plane and also in a vertical plane with respect to said roller, a rotatable finishing unit including spaced horizontally and radially disposed blades carried by said frame to follow said roller, a power unit carried by said frame and having a driving connection with said finishing miit, said, roller conditioning the cement surface preparatory to the latter'being acted upon by said blades, and means whereby said roller and said finislung unit may be adjusted bodily toward and from one another.

6. In a machine for finishing the surface of cement, the combination of a rotary finishing member, a surface leveling member, a yoke supported by and fulcrumed on said leveling memher, a frame supported by and pivoted to said yoke, said rotary finishing member being carried by said frame in rear of said leveling member, a handle for swinging said frame and determining the pressure of said rotary finishing memher, a motor carried by said frame, said motor being positioned in proximity to the leveling member thereby decreasing the static weight on the rotary finishing member.

7. A lightweight portable concrete surfacing and finishing machine comprising a skeleton frame, a roller adjacent the rear end of the frame and a rotable finishing unit adjacent the front end of the frame, the surfacing roller being disposed transversely of the longitudinal axis of the frame and mounted to swing about an upright pivot, the finishing unit comprising a plurality of blades with their work engaging surfaces convexly curved, means for driving said finishing unit, handle means connected to the rear end of the frame for operating the machine unit,

so that the surfacing roller may be used to roll out and smooth the work while the finishing unit is rotated to give a final finishing operation to the Work, the raising or lowering of the handle serving, respectively, to lighten the Weight on the roller and increase the weight on the finishing unit and to increase the weight on the roller and lighten the weight on said unit and the pivotal mounting of the roller permitting the machine to be steered over the surface being treated.

8. In a surfacing machine for cement or concrete floors, pavements and the like, a main frame, a substantially horizontally and transversely disposed surface-conditioning member carried by said frame and adapted to have a trowel-like smoothing action on the surface of the cement, and a rotatable finishing unit disposed to follow said surface-conditioning memher, said rotatable finishing unit including a plurality of spaced substantially horizontally and radially disposed blades adapted to finish the surface acted on by said conditioner.

9. In a surfacing machine for cement or concrete floors, pavements and the like, a mainframe, a substantially horizontally and transversely disposed surface conditioning member carried by said frame and adapted to have a trowel-like working action on the surface of the cement, and a rotatable finishing unit disposed to follow said surface conditioning member, said rotatable finishing unit including a plurality of spaced substantially horizontally and radially disposed blades adapted to finish the surface acted on by said conditioner, and means for adjusting the angle of said finishing blades to obtain the most effective working action thereof.

10. In a surface finishing machine for cement or concrete floors, pavements and the like, a frame, a substantially horizontally and transversely disposed roller carried by said frame, a rotatable finishing unit including a driven memher having the central or body portion thereof formed as a mounting means, and a plurality of blades secured to the body portion of said member, a motor mounted on said frame between said roller and the rotatable finishing unit in a position substantially nearer to the roller than to the finishing unit, and a drive connecting said motor with said finishing unit.

HORACE D. ALLEN. 

